© 2019 Department of Petroleum Resources. All rights reserved Department of Petroleum Resources (DPR) PROCEDURE GUIDE

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exceeds ±2 standard deviation (±2σ) on the control chart the cause of the change 
should be sought and maintenance provided.  
For this purpose, the procedure outlined in Section 3.2.3 of this guide shall be 
followed in proving all the meters in the bank for performance monitoring. 
1.9.13 In a case where the counter of a meter is found stuck, the volume/quantity of 
petroleum and petroleum product that has passed through shall be established by 
the material balance between the estimated quantity based on the pumping rate and 
the gross receipt at the tank farm downstream the meter, or for cases where the 
meter is installed between two tankages, the material balance of petroleum and 
petroleum product quantities in the two tankages over the period concerned. 
1.9.14 In a case where the meter fails during measurement operations, average meter 
factors established during the three preceding proving shall be used to estimate the 
quantity of petroleum and petroleum product passed through during the operations. 
However, if the meter failure persists after 30 days, the Department’s approval shall 
be sought for further guidance.  
1.9.15 In the case where critical instrument/part of the metering system such as four- 
way valve, flow computer etc. fails to function, Part II Section 1.9.14 shall apply for 
four (4) export liftings only. Thereafter, static measurement shall be used, and 
outturn of such export shall be verified by DPR.